Abstract: The sulfur content in high-grade non-oriented silicon steel W310 is generally required to be less than 0.002 5%. Based on the manufacturing process of " KR― BOF—>RH—^continuous casting , the mechanism of KR deep desulphurization ,converter smelting and RH powder spraying desulphurization are analyzed and studied in this paper, combined with the working conditions and raw material conditions of the 300 t steel-making system, the thermodynamic and kinetic conditions improvement measures such as optimization of hot metal composition and temperature, composition adjustment of KR and RH desulfurizer, converter heal balance control, strong bottom blowing smelting and process sulfur load control are put forward. Application results show that after optimization, the ratio of sulfur content less than 15 x 10^-6 in once KR treatment has increased from 69% to 100%, and the sulfur content after treatment has decreased from 10.48 x 10^-6 to 7.07 x 10^-6. The average sulfur content at the end point of converter is 20. 10 x 10^-6, and sulfur pick-up by 13.03 x 10^-6 during process, which are 44. 8% and 49. 8% lower than before optimization, respectively. The sulfur content of RH liquid steel decreases from 19.50 x 10^-6 to 8. 65 x 10^-6 , the dosage of desulfurizer decreases by 55.9%, and the proportion of sulfur less than 25.00 x 10^-6 increases from 90.5% to 100%, good results have been achieved.

Key words: Silicon Steel W310； Smelting； Desulphurization； Sulfur Pick-up, Thermodynamics

摘要： 高牌号无取向硅钢W310成品硫含量一般要求小于0.0025%。基于“KR铁水脱硫→顶底复吹转炉→RH真空炉→连铸”制造流程，分析研究了KR深脱硫、转炉冶炼、RH喷粉脱硫机理，结合300 t炼钢系统工况及原料条件，提出了铁水成分、温度优化，KR、RH脱硫剂成分调整，转炉热平衡控制、强底吹冶炼，工序硫负荷管控等热力学、动力学条件改善措施。应用表明：优化后KR一次处理硫含量小于15×10^-6炉次比例由69%提升到100%,处理后硫含量由10.48×10^-6下降到7.07×10^-6;转炉终点平均硫含量20.10×10^-6,过程回硫13.03×10^-6,较优化前分别降低44.8%、49.8%;RH钢液硫含量由19.50×10^-6降至8.65×10^-6,脱硫剂用量减少55.9%,硫含量小于25.00×10^-6比例由90.5%提升到100%,取得了良好的效果

关键词: W310硅钢, 冶炼, 脱硫, 增硫, 热力学